Vegan Baking

[Nemesia]

My daughter has to bake a cake for school using a prescribed recipe. The recipe is 75g flour, 75g sugar, 15g cocoa and 3 whole eggs.
Any idea on what we can replace the eggs with to get a decent cake, without changing the rest of the recipe?
So far she has tried organ egg replacer (sticky mess) and aquafaba whipped up with the sugar (moderate success but no rise as the mix collapses when the aquafaba is folded in).
Can anyone please help?

This is a handy little hack that I learnt from various baking websites. It is the perfect addition to cake, muffin and pancake recipes and is by far the most affordable option! You’ll need to use 1 tsp of baking soda with 1 tbsp of white wine vinegar or apple cider vinegar for each egg.

Half a banana per egg.
Spoon of apple sauce per egg

Thank you, I should have said that the skills she needs to show are whipping to increase volume and folding in. So although the vinegar and soda would normally work, she can't change the quantities of flour. 75g of flour does not a cake make without something else to increase the volume! So I really need something that will act like an egg in this recipe to increase volume and to make it rise.

Id be more inclined to request vegan appropriate objectives then.

Thank you Diane, I have given many suggestions, and am waiting for them to get back to me on what alternative recipe she can use, but I in the meantime I was hoping someone would have a miracle solution!
I think we have to go with the aquafaba and accept that her cake will be more pancake like than the others. Frustrating as using the right recipe, she can make beautiful vegan cakes.

I use an egg replacer when baking but always add some soy or almond milk as well, since eggs not only provide the glue effect but also moisture.
However if you have to whip it, aquafaba is usually the most similar.

I have some amazing vegan cake recipes so it's even more frustrating having to replace the eggs in this recipe without using any additional ingredients (there isn't even any fat in the recipe she has to use!).

If you get a can of garbanzo beans (and even other types of beans) the liquid from the can can be whipped by hand or with an electric mixer into a mousse. This process is called Aguafaba. The mousse that is created is an excellent egg replacement.